Baler needle safety connection



H. w. SCHAAF 2,780,164

BALER NEEDLE SAFETY CONNECTION 2 Sheets-Sheet 1 Feb. 5, 1957 Filed Oct.30, 1953 ATIORNEYS IN] 'E.\' TOR.

Feb. 5, 1957 H. w. SCHAAF 2,780,164

BALER NEEDLE SAFETY CONNECTION Filed Oct. 30, 1953 Y 2 Sheets-Sheet 2ATTORNEYS v INVENTOR. H.W. SCHAAF I al ae BALER NEEDLE SAFETY CONNECTIONHenry W. Schaaf, Lake Orion, Mich., assignor to Ford Motor Company,Dearborn, Mich., a corporation of Delaware Application October 30, 1953,Serial No. 389,207

3 Claims. (Cl. 100--19) This invention relates to automatic balingmachines. In a more specific aspect this invention relates to a safetydriving connection for the needles which wrap the twine or other bindingmedium around the compressed bales in automatic baling machines.

Baling machines are widely employed to make bales of straw, hay and thelike, for use as animal feeds, bedding and the like. Such ba lingmachines usually include a bale chamber wherein material is compressedby a reciprocable ram, and a twine or wire carrying needle is arrangedto pass through slots in a bale chamber wall and'the baler ram toposition the wire or twine around a compressed bale for. tying by theknotting device. In many instances bending and breakage have been causedsuch needles when they encounter an obstruction in the path of theirtravel. Oftentimes, due to excess vibration of the baler caused by roughfields, the needles are misaligned with the bale chamber slots andstrike the side of the bale chamber. Also the needles may get out ofsynchronization with the ram and strike the side of the ram headresulting in damage to the needles and often to other parts of thebaling mechanism.

It is accordingly an important object of the present invention toprovide a safety drive connection for baler needles. It is a furtherobject to provide a novel safety connection for baler needles whichautomatically disengages the needles from the needle driving mechanismwhen an obstruction is encountered. It is still another object toprovide a safety connection for baler needles which operates to forciblyreturn the needles to a safe position outside of the bale chamber in theevent such needles strike an obstruction or encounter an unusualresistance in their path of travel.

The specific nature of this invention, as well as other objects andadvantages thereof, will become apparent to those skilled in the artfrom the following detailed description, taken in conjunction with theattached sheets of drawings on which, by way of preferred example only,is illustrated one embodiment of this invention.

On the drawings:

Figure l is a perspective view of a baler drive mechanism embodying thesafety connection of the present invention.

Figure 2 is a plan view of the present baler needle safety connection.

Figure 3 is a section view taken along the plan of 3--3 of Figure 2.

As shown on the drawings:

Numeral refers to the bale chamber which comprises the conventionalelongated case of substantially square cross section. A ram 11 isslidably disposed within bale chamber 10 by means of wood wear blocks11a and is adapted to be reciprocated longitudinally within the balechamber. The main drive shaft 12 of the baler is adapted to be poweredfrom an external source (not shown) and is fitted with a bevel gear 12awhich meshes with a bevel gear 13, attached to an upstanding crank shaft14, for driving the same. Crank shaft 14 is dis- United, States Patent 02,780,164 Patented. Feb. .5, .1357

ICC

posed adjacent one side and exteriorly of chamber 10, and is fitted atits upper end with a crank arm 15. Gem necting rod 16 drivingly connectsthe crank arm 15 and the ram 11 for reciprocating movement. Thisconstruction is more specifically described in my copending applicationSerial No. 310,282, filed September 18, 1952.

The needle drive mechanism is indicated generally at 17 and is adaptedto actuate a set of needles 32 in synchronization with the movement ofthe ram 11. The needle drive mechanism 17 is intermittently activated bymeans of a conventional gage wheel and clutch mechanism (not shown) tomove the needles 32 across the bale chamber 10 at the end of every bale.The main drive shaft 12 has a sprocket 18 secured thereon. Alongitudinally disposed idler shaft 19 is positioned on the oppositeside of the bale chamber 10 and has a sprocket 20 secured thereto. Achain 21 drivingly connects sprockets 18 and 20 to power the idler shaft19. Shaft 19 is fitted with a bevel gear 22 and the upstanding needledrive shaft 24 is fitted at its lower end with a bevel gear 23 whichmeshes with the bevel gear 22 on idler shaft 19. Needle drive shaft 24is fitted atits upper end with a cam plate 25 which has a cam groove 25aformed therein. A bell crank 26 is pivotally mounted at 27 on top ofbale chamber 10 and has an upstanding pin 26a formed on its one endwhich is adapted to slidably engage the cam groove 25a of cam plate 25.The needles 32 and their mounting are indicated by reference numeral 29and comprise a pair of horizontally disposed arms 30 which arerespectively pivoted to the top and bottom of bale chamber 10 bysuitable pivot connections 30a. Pivots 30a are in coaxial, verticalalignment. An upstanding support rod 31 is secured between the outerends of arms 30 and is adapted to swing in an are about the axis of thevertically disposed pivots 30a. The needles 32 are rigidly secured tothe upstanding support rod 31 and are adapted to swing through suitableslots (not shown) in the wall of the bale chamber 10 and slots in theram 11 when the ram is positioned in contact with the hay.

The safety connection of the present invention is indicated by referencenumeral 28 attached by means of straight pin 37b and cotter key 30b andis clearly shown in Figures 2 and 3. Safety connection 28 provides aconnecting link between the free end of hell crank 26 and the top needlesupport arm 30 for driving the needles 32 into and out of bale chamber10. Connection 28 comprises an outer tube 33 into which a rod 35slidably telescopes. Rod 35 and outer tube 33 are provided withalignable apertures for the receipt of a shear pin 36 which normallyholds said parts in an assembled operative relationship. A shear pinindexing block 33a is welded to outer tube 33 and is provided with anaperture which is coaxial with the aperture of tube 33. Block 33a is ofsuch dimension that the neck portion or shear point 36a of pin 36 willlie in the shear plane between tube 33 and rod 35 when said pin isdriven in flush with the outer surface of said indexing block.

Rod 35 has a short tube 37 threaded onto its outer end, which is ofsubstantially the same outside diameter as tube 33. Tubes 37 and 33 arerespectively fitted with thrust washers 37a and 33b, welded thereto.Washers 37a and 33b are longitudinally spaced on the assembled unit 28.A coil compression spring 38 is fitted over tubes 33 and 37 between thewashers 33b and 37a. The ends of the unit 28 are fitted with pivot pins39 and 40 whereby said unit is connected between the free end of hellcrank 26 and the upper needle support arm 30.

Operation Since the force required to shear pin 36 is greater than theforce of spring 38 and the normal working force imposed on needles 32,caused by movement of the bale binding agent across bale chamber 10, theunit 28 is maintained in an assembled, operative relation by pin 36.However when the needles 32 encounter an unusual force or strike anobstruction in their path of travel, the additional pressure will causepin 36 to be sheared. Spring 38 being under compression, then rapidlyforces tube 33 and rod 35 apart, causing the needles 32 to be swungbackwards and clear of-bale chamber 10. Thus the safety connection 28both drives and safeguards the needles 32 against accidental damage orbreakage.

It will thus be understood that the present invention provides a novelsafety connection for driving the needles of automatic baling machines.The present connection is advantageously a functional part of themachine in that it both drives the needles and serves'as a safeguard forprotecting the needles during their operation.

It will, of course, be understood that various details of constructionmay be varied through a wide range without departing from the principlesof this invention and it is, therefore, not the purpose to limit thepatent granted hereon otherwise than necessitated by the scope of theappended claims.

I claim:

1. In a baling machine comprising a baling chamber, having an opening ina wall thereof, a needle movable through said opening and across saidchamber, and drive means for reciprocating said needle, the improvementof a safety driving connection for said needle, said connectioncomprising a separable link having a pair of halves respectivelyconnected to said needle drive means and to said needle, a shearconnection normally holding said link halves in an assembled relation,and means normally biasing said needle away from said bale chamber,whereby an obstruction in the path of said needle causes said shearconnection to be severed and said biasing means to forceably move saidhalves apart and thus move said needle to a safe position outside ofsaid bale chamber.

2. For use with an automatic baling machine having a bale chamber and aneedle movable into and out of said bale chamber, and drive means forreciprocating said needle, the improvement of a safety drivingconnection for said needle, said connection comprising a pair oftelescoping elements respectively connectable between said needle andsaid needle drive means, said telescoping elements being held in anormally fixed and nested relation by a shear connection therebetween,and means normally biasing said telescoping elements apart whereby, whensaid needles encounter an obstruction said shear connection is caused tobe severed and said biasing means forceably separates said telescopingelements to move said needle to a safe portion outside of said balechamber.

3. The needle safety driving connection defined in claim 2 wherein saidshear connection includes an apertured shear pin indexing block fixedlysecured to the outer of said telescoping elements with the said aperturecoaxial with alignable apertures in said outer and inner telescopingelements, said indexing block being of such dimension that the neckeddown shear point of a shear pin will lie in the shear plane between saidinner and outer telescoping elements when said pin is driven in flushwith the outer surface of said index block.

References Cited in the file of this patent UNITED STATES PATENTS1,384,270 Murphy July 12, 1921 1,671,966 Burkholder June 5, 19281,740,838 Roesen Dec. 24, 1929 2,485,001 Kane Oct. 18, 1949 2,512,896Hill et al. June 27, 1950 2,665,128 Guifey Jan. 5, 1954

